Push-on clips are conventional and well known in the art. Each clip comprises a relatively thin, slightly domed member of resilient metal. Each clip has a central perforation of X-shaped configuration. A workpiece, adapted to be affixed to a surface of an element, is provided with an integral post extending through a perforation in the element. A clip is forced over the post. The X-shaped perforation in the clip defines four substantially triangular lobes which are distorted in a direction opposite to the direction of movement of the clip as it passes down the post. These lobes firmly and frictionally engage the post, precluding removal of the clip, so that the workpiece is firmly affixed to the surface of the element through which its post extends.
Such push-on clips are available in strips, wherein each clip constitutes an integral, one-piece part of the adjacent clip with a line of weakening formed therebetween. The lines of weakening enable each clip, in its turn, to be broken away from its strip.
The present practice is to install such push-on clips by use of a rubber mallet, a hand-held fixture tool, or by fixed bench type systems.
Applications of such clips by hand is time consuming. In the usual procedure, the workman grasps a strip of clips, locating the forwardmost clip of the strip over the post. Once the clip has been applied, it must be severed from the strip. Sometimes in doing this, the strip does not break between the forwardmost clip applied to the post and the next adjacent clip, but rather breaks at a point a number of clips removed from the applied clip. It is not unusal for the excess clips to simply remain attached to the applied clip, the workman next applying the forwardmost clip of the strip remaining in his hand. This results in a considerable loss or waste of clips.
The present invention is based upon the discovery that a conventional, hand-held fastener driving tool can be converted for use in applying push-on clips of the type under consideration. Furthermore, the tool may be provided with a magazine holding a large quantity of such push-on clips. The magazine is easily changed and can be either refillable and reusable, or disposable, as will be apparent hereinafter.
The tandem push-on clip system of the present invention is more mobile, speeds assembly, and eases arm and hand strain. The system enables the worker to move about freely, and he is no longer tied to a fixed work station. By making the cartridge easy to change, faster application of large quantities of clips results, without loss or waste. As will be apparent hereinafter, the driver mechanism that sets the clip onto its post also is used to shear the clip from its strip and further activates a clip feed mechanism. Since the bottom of the tool guide body is exposed, the workman is enabled to positively locate and position each fastener on its respective post. The last fastener of a strip is held in position by means of a finger/spring arrangement that prevents it from dropping out of the tool.